Fuel 89 (2010) 1230–1240

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Fuel

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Transformation of CH4 and liquid fuels into syngas on monolithic catalysts

Vladislav Sadykov a,b,*, Vladimir Sobyanin a,b, Natalia Mezentseva a, Galina Alikina a, Zakhar Vostrikov a,Yulia Fedorova a, Vladimir Pelipenko a, Vladimir Usoltsev a, Sergey Tikhov a, Aleksei Salanov a,Lyudmila Bobrova a, Sergey Beloshapkin c, Julian R.H. Ross d, Oleg Smorygo e,Vladimir Ulyanitskii f, Vladimir Rudnev g

a Boreskov Institute of Catalysis, prosp. Akad. Lavrentieva, 5, 630090 Novosibirsk, Russiab Novosibirsk State University, Novosibirsk 630090, Russiac Materials and Surface Science Institute, University of Limerick, Irelandd Centre of Environmental Research, University of Limerick, Limerick, Irelande Powder Metallurgy Institute, Minsk, Belarusf Lavrentiev Institute of Hydrodynamics, Novosibirsk 630090, Russiag Institute of Chemistry, Far-Eastern Branch of Russian Academy of Sciences, Vladivostok, Russia

a r t i c l e i n f o a b s t r a c t

Article history:Received 1 June 2009Received in revised form 15 December 2009Accepted 16 December 2009Available online 1 January 2010

Keywords:Hydrogen and syngas productionGas and liquid fossil fuelsBiofuelsSteam and autothermal reformingMonolithic catalysts

0016-2361/$ - see front matter � 2009 Elsevier Ltd. Adoi:10.1016/j.fuel.2009.12.015

* Corresponding author. Address: Boreskov InstituLavrentieva, 5, 630090 Novosibirsk, Russia. Tel.: +73308056.

E-mail address: sadykov@catalysis.ru (V. Sadykov)

Active components comprised of fluorite-like Lnx(Ce0.5Zr0.5)1�xO2�y (Ln = La, Pr, Sm) and perovskite-likeLa0.8Pr0.2Mn0.2Cr0.8O3 mixed oxides and their composites with yttria-doped zirconia (YSZ) promoted byprecious metals (Pt, Ru) and/or Ni were supported on several types of heat-conducting substrates (com-pressed Ni–Al foam, Fecralloy foil or gauze protected by corundum layer, Cr–Al–O microchannel cermets,titanium platelets protected by oxidic layer) as well as on honeycomb corundum monolithic substrate.These structured catalysts were tested in pilot-scale reactors in the reactions of steam reforming of meth-ane, selective oxidation of decane and gasoline and steam/autothermal reforming of biofuels (ethanol,acetone, anisole, sunflower oil). Applied procedures of supporting nanocomposite active componentson monolithic/structured substrates did not deteriorate their coking stability in real feeds with a smallexcess of oxidants, which was reflected in good middle-term (up to 200 h) performance stability prom-ising for further up-scaling and long-term tests. Equilibrium yield of syngas at short contact times wasachieved by partial oxidation of decane and gasoline without addition of steam usually required to pre-vent coking. For the first time possibility of successive transformation of biofuels (ethanol, acetone, ani-sole, sunflower oil) into syngas at short contact times on monolithic catalysts was demonstrated. Thiswas provided by a proper combination of active component, thermal conducting monolithic substratesand unique evaporation/mixing unit used in this research.

� 2009 Elsevier Ltd. All rights reserved.

1. Introduction

Transformation of fuels (fossil fuel, biofuels) into syngas orhydrogen is one of the most important tasks of catalysis in the en-ergy-related fields [1–4]. Catalysts comprised of precious metalsand/or Ni supported on fluorite-like or perovskite-like complexoxides with a high lattice oxygen mobility are known to be veryefficient and stable to coking in reforming of a variety of fuels byusing different oxidants (oxygen, water, CO2 and their combina-tions) [5–16]. Monolithic substrates with a good thermal conduc-tivity are promising for providing an efficient heat transferwithin the reactor to prevent emergence of hot spots/cool zonesdeteriorating performance [17–24].

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te of Catalysis, prosp. Akad.383 3308763; fax: +7 383

.

Earlier we have carried out detailed studies of the effect ofchemical composition of doped ceria-zirconia fluorite-like oxidesand complex perovskite oxides (mixed chromite–manganites) pro-moted by Ni and precious metals (Pt, Pd, Ru) on their oxygenmobility and reactivity [9–14]. Different synthesis proceduresincluding polymerized polyester precursor (Pechini) route [14]and combinatorial synthesis procedures using robotic installations[10,11] were applied to optimize the composition and nanostruc-ture of these materials. Best systems selected by results of screen-ing tests in diluted feeds containing such fuels as methane, decaneor oxygenates (ethanol, acetone) were combined with traditionalcermet anode materials of solid oxide fuel cells (NiO-yttria-stabi-lized zirconia (YSZ), supported on anode platelets or metallic sub-strates and tested in steam reforming of CH4 in realistic feeds[15,17,19]. Fluorite-like ceria-zirconia solid solutions promotedby Pt or its combination with Ni selected by screening tests weresupported on structured ceramic, metallic or cermet substrates

V. Sadykov et al. / Fuel 89 (2010) 1230–1240 1231

and tested in reactions of CH4 and gasoline selective oxidation intosyngas at short contact times [8,25–31]. A high yield of syngasapproaching equilibrium values was obtained and a stable perfor-mance due to a high sintering resistance and coking suppressionwas demonstrated. A reasonable description of both steady-stateand start-up regimes of CH4 partial oxidation was obtained forreactors equipped with monolithic catalysts using different model-ing techniques [26,31]. However, for liquid fuels, especially realcomplex fuels (gasoline, diesel, etc.) and oxygenates (bio-oil,etc.), due to inherent problems of their easy decomposition andcracking at evaporation as well as mixing inhomogeneity [1–4],performance features of real-size monolithic catalysts with sup-ported nanocomposite active components have not been charac-terized in details in realistic feeds up to date. Design of a uniquemonolithic evaporator/mixer unit comprised of thick-foil Fecralloysubstrate protected by a corundum layer supported by blast dust-ing and heated by passing the electric current [24] allowed to solvethe problem of preparation of feeds with a high concentration ofsteam and liquid fuels with sufficient feed rates to test monolithiccatalysts at millisecond contact times. This for the first time pro-vides a possibility to compare performance of a series of mono-lithic/structured catalysts in realistic feeds containing differentfuels at short contact times and elucidate specificity of their actionas related to the nature of fuel, substrate and active componentwhich is certainly required for design of compact and reliable syn-gas or hydrogen generators from a variety of fuels.

This work presents results of such a comparative researchaimed at elucidating specificity of such structured catalysts perfor-mance at lab-scale and pilot-scale levels using specially designedreactors and installations allowing to broadly tune the operationalparameters (inlet temperatures and feed compositions). A specialattention was paid to new types of structured heat-conductingsubstrates comprised of compressed Ni–Al foam, Fecralloy gauzesand microchannel washers protected by refractory corundum lay-ers. As for nanocomposite active components, systematic studies oftheir coking stability in feeds with broadly different coking poten-tial (methane, decane, gasoline, ethanol, acetone and sunflower oil)is apparently of a great fundamental and practical interest.

2. Experimental

2.1. Structured catalysts preparation

2.1.1. Nanocomposite active componentsNanocomposite active components were comprised of complex

fluorite-like oxides Lnx(Ce0.5Zr0.5)1�xO2�y (Ln = La, Pr, or Sm, x = 0–0.3) or perovskite-like oxides La0.8Pr0.2Mn0.2Cr0.8O3 prepared viamodified Pechini route [12,14]. In some cases, to improve sinteringresistance, nanocomposites of fluorite-like or perovskite-like oxi-des with YSZ were prepared using powdered Y0.08Zr0.92O2�y (Rus-sian source) electrolyte. YSZ powder was first dispersed in thewater solution of polyester citric acid–ethylene glycol polymericprecursor of perovskite like or fluorite-like oxide following so-called one-pot synthesis routine [12]. In some cases, up to30 wt.% NiO was incorporated into this nanocomposite by addingrequired amount of Ni nitrate into suspension of 8YSZ in the poly-meric precursor. After evaporation, formed solid residue wasdecomposed in air at 500 �C and then calcined at 700 �C for 4.Details of these active components synthesis and characterizationare given elsewhere [12,14,15].

2.1.2. Structured substrates/supports and catalystsCeramic monoliths (hexagonal side 28 mm, monolith length

50 mm, wall thickness 0.25 mm, equivalent channel diameter

1.9 mm, surface area 3–10 m2/g) were prepared by plastic extru-sion and sintered at 1200 �C [18].

Composite cermet monoliths (up to 46 mm diameter, ca. 300cpsi channel density, ca. 0.3 porosity) were prepared by hydrother-mal treatment (HTT) of the mixture of Cr–Al alloy in a special typeof die followed by calcination in air at 1200 �C. To form a setof transport channels (a row of parallel passageways �0.5 mmdiameters along the substrate monolith interconnected bynarrow �0.1 mm anfractuous channels separated by ca. 0.05 mmwalls), easily burned organic fibers were inserted into the cermetmatrix before HTT [22].

Open-cell nickel foams were manufactured by the nickel elec-troplating of the polyurethane foam samples (thickness 5 mm,the cell density 60 ppi) followed by sintering in the dissociatedammonia atmosphere at 1100 �C for 1 h. The foam samples werethen deformed by a uniaxial compression to 1 mm thickness mod-ifying the cell morphology and decreasing porosity from 95.5% to50–80%. Deformed foams were subjected to the pack aluminizingand then annealed at 1000 �C for 1 h under air to form a thin corun-dum layer over the foam cell walls for a better adhesion of catalyticlayers.

Fecralloy foil substrates (thickness 20–200 lm) were protectedby supporting a thin (ca. 5–10 lm) corundum sublayer by blastdusting technique [24]. Monolithic substrates were obtained viastacking a flat and corrugated foils and winding them into anArchimedes spiral. After spark-welding tungsten rods as electriccurrent inlets, thick-foil monolithic substrate (diameter 55 mm,length 20–45 mm, triangular channels with side ca 3 mm) wasused for evaporation and mixing of water and liquid fuels sprayedvia a nozzle onto its front part.

Thin-foil Fecralloy monolithic substrate (surface area 4700 m2/m3, channel size �1.2 mm, porosity ca. 0.8) was precovered by sec-ondary Ce–Zr–La–O mixed oxide support via a standard washcoat-ing procedure using an alumina hydroxide as a binder and calcinedat 1000 �C.

The Fecralloy gauze substrate (woven from the wires with diam-eter 0.2 mm and ca. 0.2 mm spacing) was first precovered by a thin(ca. 5–10 lm) corundum sublayer by blast dusting technique [24]followed by washcoating with La-stabilized c-Al2O3 (3.6 wt.%) froman appropriate suspension followed by calcination under air at1100 �C for 2 h. Before supporting active components, the gauzewas either cut into square pieces (to be stacked with Ni–Al foamplates, Table 1) or winded into cylindrical substrates with a distance�0.1 mm between neighboring layers (Table 1, samples 1–3, 6).

A central part of the radial-flow reactor used in this work con-sisted of 60 Fecralloy washers (outer diameter 38 mm, inner diam-eter 19, height 2 mm) piled up in a cylinder by means of nutbolting. Multiple radial channels (0.5 mm depth and 0.5 mmwidth) were milled in the washer planes with the angular stepwidth of 4 degrees, resulting in 90 channels on a side. Protectivecorundum layer on these washers was supported by blast dusting.

Ti platelet substrates (samples 12, 13) were covered withCe–Zr–Ti–O protective layer by using specific electrochemicaloxidation procedures developed at the Institute of Chemistry,Far-Eastern Branch of Russian Academy of Sciences [32].

To prepare samples 1–10, 12–14 (Table 1) as well as to supportactive component on microchannel washers and layers of gauzes inthe radial reactor (vide infra), powders of nanocomposite complexoxides were ultrasonically dispersed in isopropyl alcohol withaddition of polyvinyl butyral as a binder to make a slurry. Thin lay-ers of composites were supported on substrates using these slur-ries followed by drying and calcination at 1100 �C after eachsupporting step until loading of 4–7 wt.% was achieved. Preciousmetals (Pt, Ru) or LaNi(Pt)O3 (up to 10 wt.%) were supported bythe incipient wetness impregnation followed by drying and calci-nation under air at 800 �C.

Table 1Basic types of monolithic catalysts.

No Sample description

Type of substrate Active component composition and loading (wt.%)

1 FeCrAl gauze (cylinder D 15 mm, L 26 mm) 5.9 Pr0.3Ce0.35Zr0.35�2 + 0.92 Pt2 The same as 1 5.9 Pr0.3Ce0.35Zr0.35O2 + 7 LaNi(Pt)O3 (1.2 Pt)a

3 The same as 1 6.6 Pr0.3Ce0.35Zr0.35O2 + 1.3 Pt + 0.3 Ru4 FeCrAl foil 20 lm (cylinder D 15 mm, L 26 mm) 5.5 Pr0.3Ce0.35Zr0.35O2 + 1.2 Pt5 The same as 4 6.3 Pr0.3Ce0.35Zr0.35O2 + 1.0 Pt6 FeCrAl gauze (the same as 1) 5.4 La0.1Ce0.45Zr0.45O2 + 10 LaNi(Pt)O3 (1 Pt)a

7.0 Ni–Al compressed foam (plate 10 � 20 � 1 mm), density 2.5 g/cm3 4% (50 La0.8Pr0.2Mn0.2Cr0.8O3 + 30 NiO + 20 YSZ) + 0.7Ru7.1. Ni–Al compressed foam (plate 10 � 20 � mm), density 0.4 g/cm3 26 (50 La0.8Pr0.2Mn0.2Cr0.8O3 + 30 NiO + 20 YSZ) + 6.51 Ru7.2. Ni–Al compressed foam (plate 10 � 20 � 1 mm), density 1.17 g/cm3 13.84 (50 La0.8Pr0.2Mn0.2Cr0.8O3 + 30 NiO + 20 YSZ) + 2.99 Ru7.3. Ni–Al compressed foam (plate 10 � 20 � mm), density 1.28 g/cm3 10.2 (50 La0.8Pr0.2Mn0.2Cr0.8O3 + 30 NiO + 20 YSZ) + 1.44 Ru7.4. Ni–Al compressed foam (plate 10 � 20 � 1 mm), density 1.37 g/cm3 11.64(50 La0.8Pr0.2Mn0.2Cr0.8O3 + 30 NiO + 20 YSZ) + 2.38 Ru7.5. Ni–Al compressed foam (plate 10 � 20 � 1 mm), density 1.39 g/cm3 9.56 (50 La0.8Pr0.2Mn0.2Cr0.8O3 + 30 NiO + 20 YSZ) + 2.59 Ru7.6. Ni–Al compressed foam (plate 10 � 20 � 1 mm), density 1.79 g/cm3 10.73 (50 La0.8Pr0.2Mn0.2Cr0.8O3 + 30 NiO + 20 YSZ) + 2.83 Ru7.7. Ni–Al compressed foam (plate 10 � 20 � 1 mm), density 2.23 g/cm3 7.3 (50 La0.8Pr0.2Mn0.2Cr0.8O3 + 30 NiO + 20 YSZ) + 2 Ru7.8. Ni–Al compressed foam (plate 10 � 20 � mm), density 2.26 g/cm3 7.43(50 La0.8Pr0.2Mn0.2Cr0.8O3 + 30 NiO + 20 YSZ) + 1.59 Ru7.9. Ni–Al compressed foam (plate 10 � 20 � 1 mm), density 2.49 g/cm3 6,64(50 La0.8Pr0.2Mn0.2Cr0.8O3 + 30 NiO + 20 YSZ) + 1.3 Ru8 CrAlOy/CrAlx cermet (cylinder D 19 mm, L 21 mm, 20 channels) 3.3 (Ce0.35Zr0.35Sm0.15Pr0.15O2 + 1.5 Ru)9 FeCrAl foil 200 lm (D 53 mm, L 12.5 mm) 2 La0.1Ce0.45Zr0.45O2 + 1 LaNi(Pt)O3 (0.1Pt)a

10 FeCrAl foil 20 lm (D 50 mm, L 50 mm) 10 La0.1Ce0.45Zr0.45O2 + 7 LaNi(Pt)O3 (1Pt)a

11 Corundum honeycomb monolith, (D 50 mm, L 50 mm) 10 La0.1Ce0.45Zr0.45O2 + 7 LaNi(Pt)O3 (1 Pt)a

12 Ti platelet (0.5 � 5 � 10 mm) with Ce–Zr–Ti–O protective layer 0.44 Pt + 5 Ce0.35Zr0.35Sm0.15Pr0.15O2

13 Ti platelet (0.5 � 5 � 10 mm) with Ce–Zr–Ti–O protective layer 5 (10NiO + 10YSZ + 80 Ce0.35Zr0.35Sm0.15Pr0.15O2)14 Ni–Al compressed foam substrate, density 2.5 g/cm3 5.3 (50% LaMnCrPr + 30% NiO + 20% YSZ) + 0.85 Ru

a Total Pt content in monolithic catalyst.

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Monolithic catalyst on corundum honeycomb substrate (sample11, Table 1) and microspherical LaNiPt (9 wt.%)/Ce–ZrOx (ca.12 wt.%)/c-Al2O3 catalyst (1 mm diameter spheres, BET surfacearea 150 m2/g) used for filling the space between the layers ofgauzes in the radial-type reactor (vide infra) were prepared bywet impregnation with the appropriate solutions followed by cal-cination under air at 900 �C.

A stack comprised of 12 Ni–Al-foam plates and 11 sheets ofFecralloy gauzes (volume 34 � 34 � 34 mm3) loaded with 4%(50La0.8Pr0.2Mn0.2Cr0.8O3 + 30NiO + 20 YSZ) + 0.7Ru was preparedusing procedures described above.

2.2. Reactors and testing procedures

2.2.1. The axial-flow reactorThe apparatus and procedures for oxidative reformation of such

fuels like methane, isooctane and gasoline in the monolithic reac-tors have been described elsewhere [27–31]. Catalytic monolithsfixed in a tubular quartz reactor (�300 mm long and 60 mm innerdiameter) were placed into a stainless steel reactor of a bigger sizeequipped with the heating coils to tune independently the catalysttemperature. To prevent the feed slip along the monolith walls,corundum fiber insulation was used. To reduce the radiation heatloss, 10 mm long piece of blank corundum monolith was placedin front of catalytic monoliths. Chromel–alumel thermocoupleswere used to monitor the temperature at various positions alongthe reactor length. To place a stack of Ni–Al foam plates and Fecr-alloy gauzes or a small diameter monolithic piece into a tubularreactor of 60 mm inner diameter, specially designed stainless steeland quartz insertion pieces were manufactured and used.

The fuel feed was delivered to the reactor through a stainlesssteel tube placed into a furnace to preheat it independently or pre-vent water/fuel condensation. The total flow rate of the feed (fuel,air, and steam) to the reactor was varied between 1 and 24 m3/h(STD). Contact time was estimated as catalyst volume divided bythe flow rate at a standard temperature and pressure (STP).

The steady-state activity of platelets with a typical size 1–2 cmin CH4 SR was estimated in He- or Ar-diluted feeds with CH4 con-centration up to 20% and steam/methane ratio 1–3 using specially

designed flat-wall quartz reactors. In this case, to prevent the slip,the feed flows along the sides of a platelet within a narrow(�0.2 mm) space. The contact time was varied in the range of10–70 ms as estimated by the length of plate and superficial veloc-ity related to STP.

2.2.2. The radial-flow reactorThe autothermal radial-flow reactor system [30] includes a

multiple catalyst beds of a cylindrical architecture correspondingto a total volume of about 580 cm3 (a stack of catalytic microchan-nel washers 106 cm3, gauze catalyst bed 134.0 cm3, microsphericalcatalyst bed 340 cm3). The feed enters the central part of the stackof microchannel washers and flows in the radial direction. Thus,the velocity of the gas is highest at the inlet and then decreasesto the periphery of the catalytic layers. The reformed gas was col-lected into a plenum around the catalyst arrangement and exitedfrom a single pipe.

2.2.3. Testing proceduresTo control the inlet feed flow rates and composition, pure gases

(CH4, N2, O2, Ar) and air entering from a high-pressure host systemwere adjusted using mass-flow controllers. The liquid fuels anddistilled water or their mixture were sprayed via a pneumatic noz-zle onto a heated by electric current evaporation monolithic unit(vide supra) and mixed here with gas components of the feed.

All tested single fuels were of the chemical pure grade. Thetested gasoline contained 191 types of hydrocarbons with amountof aromatics about 40 wt.%. According to analysis data [27], theaveraged composition of gasoline required for estimation of a stoi-chiometric air/fuel ratio in the feed corresponds to C7.2H13.36.

The molar ratios of H2O/C and O2/C in the feeds were varied inthe range of 1–7 and 0–0.6, respectively. Before testing in all reac-tions and reactors, samples were pretreated in O2 at 500 �C for 1 h.For reactions of steam and autothermal reforming, experimentswere typically started at high (�800 �C) temperatures and sampleswere kept at least 1 h at each temperature and/or feed rate to ob-tain steady-state results reproducible within at least day-long testsreported in this work. For reactions of selective oxidation of hydro-carbons at short contact times start-ups were carried out by

V. Sadykov et al. / Fuel 89 (2010) 1230–1240 1233

switching the stream of heated air through reactor to that of fue-l + air at a minimum feed rate [31]. After reaction ignition and tem-perature profile stabilization along the reactor, exit gas wasanalyzed and steady-state values of reagents and products concen-tration in effluent not changing for at least 1 h were taken as per-formance characteristics.

The product composition was determined by gas chromatogra-phy (TCD, FID). A fraction of product gas was taken immediatelybeyond the monoliths package. The carbon balance was 100 ± 5%.

Equilibrium composition of the reacting system was calculatedby Gibbs free energy minimization method using HYSYS simulatorsoftware with a due regard for experimentally detected products inthe effluent.

Fig. 1. A sum of CO + H2 concentration in the effluent (H2/CO � 7) for small piecesof monolithic catalysts on Fecralloy substrates (numbering as in Table 1) tested inCH4 SR. Feed CH4 + H2O (CH4/H2O = 0.8), contact time 0.06 s, Tinlet 750 �C.

3. Results and discussion

3.1. Methane

3.1.1. Small monolithic pieces in feed with steam/methane ratio �1In studied range of contact times s, at 750 �C, CH4 conversion

varies in the range of 10–30% as dependent upon the s and samplenature. The difference of temperature between the front and rearpart of small monolithic pieces was kept below 10 �C by a propertuning of heating coils operation regime. Due to a high concentra-tion of methane and a small excess of steam, testing in these con-ditions provides a fast and tough proof of the coking resistance ofnanocomposite active components selected as promising by the re-sults of studies at lower (8–20%) concentrations of methane [11–15,17,19]. For traditional Ni–YSZ anode composite material, at700 �C in the feed with steam/methane ratio 3, CH4 conversiondropped from �50% to �2% within 10 h [33]. However, in ourexperiments, for fluorite-like complex oxides supported on corun-dum-protected Fecralloy foil or gauze substrates and promoted byprecious metals and/or lanthanum nickelate, stable performancewithout deterioration due to coking was observed even in stoichi-ometric concentrated feed for days-long tests (10–20 h on stream).This confirms inherent stability of these optimized active compo-nents to coking earlier proved by both temperature-programmedoxidation experiments of samples discharged after reaction[11,12,15] as well as by transmission electron microscopy andscanning electron microscopy studies [15,19]. This was explainedby a high efficiency of complex oxides in activation of water mol-ecules and a fast transfer of oxygen-containing species to the me-tal-support interface thus providing fast gasification of CHx speciesgenerated by CH4 dissociation on surface sites.

For the same type of active component, a higher concentrationof H2 and CO (syngas) in effluent was observed for catalysts ongauze substrates (Fig. 1). This can be explained by a higher geomet-ric surface per the unit volume for monolithic pieces made fromgauzes due to more dense packing of gauze layers as well as by ahigher geometric surface area of a gauze sheet compared to thatof a foil (vide supra).

Addition of Ru to Pt was found to decrease syngas concentrationin the effluent (cf. catalysts 1 and 3). This agrees in general with alower activity of Ru-promoted fluorite-like oxides as comparedwith Pt-promoted ones [9]. Moreover, detailed studies of methanesteam reforming on supported Pt group metals by Wei and Iglesia[34] reliably demonstrated much lower specific activity of Ru ascompared with Pt. Hence, decoration or dilution of supported Ptclusters by Ru atoms is expected to decrease their activity in CH4

steam reforming which is indeed observed in our case.LaNiO3 oxide precursor for lanthana-decorated Ni particles pro-

moted by Pt demonstrates a good performance in the case of itscombination with both Pr–Ce–Zr–O and La–Ce–Zr–O fluorite-likeoxides (cf. catalysts 2 and 6, Fig. 1). Synergetic action of Pt and

Ni in CH4 steam reforming was earlier observed for promotedNiO/YSZ anode composite materials and explained by such factorsas formation of Ni–Pt surface alloys or mixed clusters stable to cok-ing as well as by participation of Ni atoms in water molecules acti-vation by redox cycles [12,15].

The increase of contact time from 0.06 to 0.17 increases hydro-gen concentration in the effluent from �15 to �30% for the mostactive sample 2, which agrees with effective reaction order closeto 1 for CH4 SR at moderate conversion levels [33–35].

3.1.2. Planar catalytic elements based on Ni–Al compressed foamsubstrates in feed with steam/methane ratio �2

For this type of substrate, another promising nanocompositematerial comprised of complex perovskite-like oxide combinedwith YSZ and Ni and promoted by Ru was selected for more de-tailed studies based upon results of previous experiments[9,15,17,19]. In this system, both perovskite-like oxide and Ru playan important role in coking suppression and providing a high activ-ity at decreased temperatures [9]. Developed porosity combinedwith a high mechanical strength and corrosion resistance makesthis type of substrate especially attractive for such application asdesign of metal-supported anodes in the intermediate temperaturesolid oxide fuel cells (IT SOFC) operating in the regime of internalreforming of methane [17,19]. To provide thermal expansion com-patibility both with substrate and traditional Ni–YSZ anode mate-rial, nanocomposite active component contains rather largeramount of Ni as compared with active components based on fluo-rite-like oxides (vide supra).

As follows from Fig. 2a, this type of active component provides areasonable level of CH4 conversion at short contact times in theintermediate temperature range (600–700 �C) which is requiredfor this application. Supporting this active component on the foamsubstrate does not affect the temperature dependence of conver-sion up to 650 �C, which implies the absence of any noticeable ef-fects of mass transfer limitation within the pores of substrate.

Tests for more than 200 h time-on-stream demonstrated a rea-sonable performance stability of this structured catalyst in CH4 SRat short contact time in the intermediate temperature (IT) range(Fig. 2b) which is required for the practical application. Thoughcertainly much longer tests are required to assess stability underreal conditions of in-cell operation, note that at a bigger excessof steam (and even with some addition of H2), for all known types

Fig. 2a. Temperature dependence of CH4 conversion in CH4 SR for (1) 0.25 mmfraction of nanocomposite active component 50% La0.8Pr0.2Mn0.2Cr0.8O3 + 30%NiO + 20% YSZ + 0.7% Ru and (2) the same active component supported oncompressed Ni–Al foam platelet (catalyst 7.0, Table 1). Contact time 10 ms for afraction and 20 ms for catalyst 7; feed 20% CH4 + 40% H2O in Ar.

Fig. 2b. Variation of CH4 conversion with time-on-stream at 650 �C for nanocom-posite active component La0.8Pr0.2Mn0.2Cr0.8O3 + NiO + YSZ + Ru supported on com-pressed Ni-Al foam platelet (catalyst 14, Table 1). Contact time 50 ms, feed 20%CH4 + 40% H2O in Ar.

Fig. 3a. Temperature dependence of CH4 conversion in CH4 SR for catalysts basedon nanocomposite active component La0.8Pr0.2Mn0.2Cr0.8O3 + NiO + YSZ + Ru sup-ported upon Ni–Al foam substrates with a different density (Table 1). Contact time50 ms, feed composition 20% CH4 + 40% H2O in Ar.

Fig. 3b. Effective first-order rate constants of CH4 SR for catalysts based upon Ni-Alfoam substrates (Table 1). Contact time 50 ms, feed composition 20% CH4 + 40% H2Oin Ar.

1234 V. Sadykov et al. / Fuel 89 (2010) 1230–1240

of Ni-containing catalysts, deactivation caused by coking and sin-tering (if observed) usually proceeds at a time scale of 10–20 h[6,8,33]. Hence, our tests at least demonstrate that our structuredcatalysts with nanocomposite active components are promisingfor further up-scaling.

To check effect of the foam Ni–Al substrate characteristics onperformance of these structured catalysts in steam reforming ofmethane, substrates with broadly varying density were preparedand loaded with the same active component (Table 1, samples7.1–7.9). There is a certain trend in decreasing the loading of activecomponent with increasing substrate density when using the samesuspension and number of supporting cycles (3 in this case). As fol-lows from the Fig. 3a, the temperature dependence of CH4 conver-sion is rather similar for samples based on different density

substrates. Rather steep temperature dependence of conversionsuggests a high apparent activation energy, and, hence, a small(if any) effect of the heat and mass transfer on these catalysts per-formance. Though kinetics of CH4 reforming on our nanocompositecatalysts supported on different substrates [19] was satisfactorilydescribed in the frames of a scheme suggested by Xu and Froment[36], in the first approximation, a simplified approach of the first-order rate equation used by King et al. [33] for analysis of thisreaction on Ni–YSZ composite could be useful at least for estima-tion of any possible impact of heat and mass transfer processes.Here, the reaction rate r is defined as r = k[CH4], where k = �(1/s)ln(1 � XCH4) is the effective first-order rate constant estimatedfrom this integral equation for the plug-flow reactor by using thevalues of CH4 conversion (XCH4) [33]. Similar approach was usedin our works to compare specific activities of nanocomposite active

V. Sadykov et al. / Fuel 89 (2010) 1230–1240 1235

components supported on different substrates in the reactions ofCH4 partial oxidation, steam and dry reforming [9,12,15,25,26].For sample 7.9 with the highest density of Ni–Al foam substrate(Table 1), estimation of apparent activation energy from the tem-perature dependence of the first-order rate constant gives value�100 kJ/mol, which is rather close to 110–120 kJ/mol estimatedby King et al. [33] and �100 kJ/mol found by Wei and Iglesia [35]for Ni/MgO system. This implies the absence of any noticeable heatand mass transfer effects on performance of designed structuredcatalysts.

For samples with different density of substrates, specific effec-tive first-order rate constants related to the unit weight of activecomponent were calculated and compared in Fig. 3b for two tem-peratures. The trend observed in this case can be explained by apartial inaccessibility of the active component located within theinterior of platelets with an intermediate density, while it is fullyaccessible for substrate with the lowest density. For the densestsubstrates, the increase of the specific rate constant seems to beprovided by the preferential location of supported active compo-nent at the exterior of platelets as revealed by SEM with EDX anal-ysis (not shown for brevity). Hence, foam substrates with thehighest density are preferable from the point of view of a highermechanical strength and thermal conductivity as well as an opti-mum spatial distribution of active component.

3.1.3. A stack of planar catalytic elements in feed with steam/methaneratio �2

To check the effect of up-scaling the size of structured catalystson their performance in the reaction of methane steam reforming,a package comprised of stacked foam platelets and gauzes wastested in feeds with or without addition of a small amount of air.In this case, the temperature difference between the front and rearend of the package was in the range of 50–70 �C which apparentlyindicates existence of the temperature gradient within the pack-age. Hence, detailed analysis of these data required a proper mod-eling with a due regard for the heat transfer within this package. Atleast, as judged by the values of CH4 conversion (50–60% withinstudied range of exit temperatures) and hydrogen content in the

Fig. 4. Temperature dependence of H2 (1, 2) and CO (3, 4) content in effluent for thereaction of steam (1, 3) or oxy-steam (2, 4) reforming of CH4 on a stack comprised of12 Ni–Al-foam plates and 11 sheets of Fecralloy gauzes loaded with La0.8Pr0.2Mn0.2-Cr0.8O3 + NiO + YSZ + Ru (volume 34 � 34 � 34 mm3). Feed 31% CH4 + H2O (H2O/CH4 = 1.9) in Ar (1, 3) or 31% CH4 + H2O (H2O/CH4 = 1.9) + 1.5% O2 in Ar (2, 4),contact time 0.15 s.

effluent (>45%, Fig. 4), performance of this package is rather good.Tests for 100 h with start-up and shut-down of pilot installationeach day (8 h working time per day) confirmed stability of this le-vel of H2 content in effluent (details not shown for brevity). Notethat at the same contact time and in the same installation, meth-ane conversion and hydrogen content were lower for smallermonolithic pieces with nanocomposite active components basedupon fluorite-like oxides (vide supra). This can be explained bythe positive effect of a moderate steam excess on the rate of meth-ane steam reforming observed for these types of active compo-nents [9,15,17,19]. On the other hand, addition of 1.5% O2 intothe feed decreases methane conversion to 30–40%, which is re-flected in the decrease of both H2 and CO content in the effluent(Fig. 4). This can be explained by oxidation of a part of active com-ponent in the inlet part of the layer, thus suppressing its activity insteam reforming reaction. Indeed, after removing oxygen from thefeed, H2 and CO content in the feed returned to the steady-state le-vel within an hour.

3.2. Liquid fuels

For liquid fossil fuels such as decane or gasoline, the most clearadvantage of structured catalysts on heat-conducting substrates isin the case of partial oxidation or autothermal reforming reactions[1–4,20,21]. This is determined by a very fast oxygen consumptionin the inlet part of the reactor, so the heat generated by combus-tion reaction is to be transferred along the catalytic bed to be con-sumed by endothermic reactions of steam and dry reforming.Heat-conducting substrates allowing to minimize the temperaturedifference between the inlet part of the layer and its main part helpto prevent thermal shocks and stresses leading to cracking of cera-mic monolithic substrates.

3.2.1. DecaneFig. 5 presents results obtained in the axial reactor for the cat-

alyst N 9 based on a thick Fecralloy foil substrate. In all experi-ments, the exit temperature was �1000 �C. Even at very shortcontact time, syngas yield is rather high. The main by-product ismethane formed via cracking reactions. At the longest contact time12 ms, concentrations of H2 (21%) and CO (24%) in the effluent

Fig. 5. CO and H2 content in effluent versus contact time for partial oxidation ofdecane on the catalyst 9 (Table 1) in the axial-type pilot reactor. Feed composition3% of decane in air (O2/C = 0.6), inlet feed temperature 180–200 �C.

Fig. 7. CO and H2 content in effluent versus contact time for the partial oxidation ofgasoline on the catalyst 9 alone (contact time range marked by ‘‘foil”) and its stackwith catalyst 11 (contact time range marked by ‘‘corundum honeycomb” (Table 1).Feed composition 4.7% of gasoline in air (O2/C = 0.48), inlet feed temperature 180–200 �C, exit temperature �1000 �C.

1236 V. Sadykov et al. / Fuel 89 (2010) 1230–1240

coincide with the equilibrium values (20% and 23%, respectively),with CH4 admixture�0.3%. At the shortest contact times, H2/CO ra-tio is somewhat lower, perhaps, due to a higher content of meth-ane (�4%) and olefins (�2) in the effluent.

In the radial reactor, in the steady-state mode, the temperatureof feed before the reactor was kept at a nearly constant level of110–120 �C. The temperature measured by thermocouple situatedin the inlet of the central part of the stack of microchannel washersdecreased from 180 to 130 �C with the increase of feed rate from1.3 to 4.0 m3/h (STP) due to cooling by the inlet stream (Fig. 6).The temperature measured by thermocouple situated after thelayer of gauzes wound around the stack of washers goes throughthe maximum at �800 �C with increasing the feed rate. The maxi-mum temperature within the microchannels in the stack of wash-ers is expected to be �1000 �C as judged by results with a shortpiece of monolithic catalyst tested in the axial reactor (vide supra).Hence, the temperature profile within the radial reactor is con-trolled by the balance between the rate of heat generation due tooxygen consumption within the stack of microchannel washersand the rates of its transfer to gauzes (increases with the flow rate)and consumption by endothermic reactions of steam and dryreforming on gauzes and within the layer of microspherical cata-lyst. This seems to determine both the increase of syngas yieldwith the feed rate and a higher content of hydrogen and CO (aswell as higher H2/CO ratio in the effluent) as compared with thecase of the axial-type reactor (cf. Figs. 5 and 6). In all studied rangeof feed rates, CH4 content in the effluent was �0.2–0.5%. Similarfeatures-the increase of syngas content in the effluent with thefeed rate were earlier observed for the partial oxidation of methaneinto syngas in this axial-type reactor [30].

3.2.2. GasolineReformulated gasoline transformation was studied for the cata-

lyst based on thick Fecralloy foil substrate (N9 in Table 1) and onthe package including this catalyst in the inlet part and a honey-comb monolithic catalyst on corundum substrate (N 11, Table 1)as the main part of the catalytic layer. As follows from results pre-sented in Fig. 7, for the layer comprised of only foil-supported cat-alyst, there is certainly a trend of decreasing CO and H2 content inthe effluent with increasing the contact time. This suggests that atvery short contact times CO and H2 are primary products of fast

1.0 1.5 2.0 2.5 3.0 3.5 4.0

20

22

24

26

Con

cent

ratio

n, %

Feed rate, m3/h

H2

CO

180/740

160/800

130/760

Fig. 6. CO and H2 content in effluent versus feed rate for partial oxidation of decanein the radial-type reactor. Feed composition 3% of decane in air (O2/C = 0.6), the feedtemperature after evaporator/mixer 110–120 �C. The ratio between temperatures inthe inlet part of reactor and after a layer of gauzes is indicated in the figure for eachfeed rate (see text).

transformation of hydrocarbons in the presence of gas-phase oxy-gen. The increase of contact time for combined catalytic layer in-creases syngas yield approaching it to the limit corresponding toequilibrium at the exit temperature (�1000 �C) (24% H2 and 26%CO). A similar close to equilibrium syngas yield was obtained formonolithic catalysts on thin-foil Fecralloy or microchannel cermetsubstrates [29].

In all these reactions of liquid hydrocarbon fuels selective oxi-dation, performance was stable with the time-on-stream for atleast 10–200 h including pilot-scale testing in real syngas genera-tors [37]. New types of nanocomposite active components, applica-tion of electric current heated evaporation/mixing unit designed inthis work and placing in the inlet part of catalytic layer structuredcatalysts with a high thermal conductivity allowed to achieve ahigh yield of syngas at short contact time and provide a stableperformance even without adding steam to the feed which wasearlier considered to be inevitable for providing a stable perfor-mance without degradation for such complex fuels as gasoline[1–4].

3.2.3. EthanolIn the reaction of ethanol steam reforming, the highest perfor-

mance was demonstrated by Pt + Ni-containing catalysts (Fig. 8),ensuring a high yield of syngas even at short contact time. This cer-tainly correlates with the performance of the same catalysts insteam reforming of CH4 (vide supra). With a due regard for themechanism of ethanol steam reforming on Ni-containing catalystsformulated by Busca et al. [38], which includes decomposition ofacetate intermediate producing CO and CH4, a high activity of cat-alysts in CH4 steam reforming is indeed expected to be required fora high rate of ethanol steam reforming. Presence of ethylene inproducts (Fig. 9) indicates that, despite a rather low acidity ofthe surface of Pr- and La-doped ceria-zirconia oxides, dehydrationof ethanol occurs. Though this by-product was observed in the caseof Pt(Ru)-promoted doped ceria-zirconia supported alumina cata-lysts [10], it was not detected for unsupported nanocomposite0.9 wt.% Ru/Pr0.15Sm0.15Ce0.35Zr0.35O2/NiO + YSZ sample [11].Hence, appearance of C2H4 in products of ethanol SR on small

2.0 2.4 2.8 3.2 3.6 4.00

1

2

51015202530

C2H4

CO2

Con

cent

ratio

n, %

H2O/C2H5OH ratio

H2

CO

CH4

Fig. 9. Effect of the H2O/C2H5OH ratio in the feed on product concentrations inethanol SR on catalyst 2 (Table 1) 750 �C, contact time 0.085 s, feed composition10% EtOH + H2O + N2 balance.

Fig. 10. Effect of C2H5OH content in the feed on product concentrations in ethanolSR on catalyst 8 (Table 1) 750 �C, contact time 0.1 s, feed composition EtOH +H2O + N2 balance, H2O/EtOH = 3.2.

31 2 4 5 60

5

10

15

20

25

30

35

H2

+ C

O, %

Sample

Fig. 8. A sum of CO + H2 concentration in the effluent for small pieces of monolithiccatalysts on Fecralloy substrates (numbering as in Table 1) tested in ethanol SR.Feed 10% EtOH + H2O in N2, H2O/C2H5OH = 3.2, 750 �C, contact time 0.085 s.

2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.501234

10

15

20

25

30

Con

cent

ratio

n (%

); H

2/C

O, (

H2+

CO

)/EtO

H

H2O/EtOH

H2

EtOH

H2/CO

(H2+CO)/EtOH

Fig. 11. Effect of H2O/C2H5OH ratio on product concentrations in ethanol oxy-steam reforming on catalyst 10 based upon thin-wall Fecralloy monolithic substrate(sample 10, Table 1). Inlet feed: 7% O2 + H2O + EtOH + N2 balance, T inlet 700 �C,contact time 0.3 s.

V. Sadykov et al. / Fuel 89 (2010) 1230–1240 1237

monolithic peaces could be assigned to the effect of the secondaryLa-stabilized alumina sublayer supported on these gauzes (vide su-pra). Note, though, that Resini et al. [16] observed C2H4 as mainproduct of EtOH SR on YSZ, while it disappears for Ni(Co)/YSZ cer-mets. de Lima et al. [39] also detected ethylene (selectivity up to5%) in the products of ethanol steam reforming on Pt/CeZrO2 cata-lyst despite a lower acidity and much higher oxygen mobility andreactivity of CeZrO2 oxide as compared with YSZ or alumina.Hence, acid sites of YSZ or even CeZrO2 support are also quite ac-tive in the process of ethanol dehydration, and only subsequenttransformation of ethylene on the metal component decreases itscontent in the products. So, it is possible that in our case, ethyleneappears in products due to ethanol dehydration on doped ceria-zir-conia oxides. The increase of steam/carbon ratio nearly completelyeliminates this admixture of C2H4 (Fig. 9), apparently due to a highredox reactivity of nanocomposite active component. At contacttimes � seconds and temperatures �800 �C, for feeds with EtOHconcentration 10%, concentrations of H2 and CO in effluent ap-proach 48% and 16%, respectively, which are close to the equilib-rium values [40].

Complex oxide active component promoted by Ru (sample 8,Table 1) demonstrates also a high and stable performance whensupported on the cermet substrate. In this case C2H4 is also ob-served in products in amounts comparable with those for gauze-supported catalysts (<1.5% at 750 �C and H2O/C2H5OH > 3). How-ever, for all types of our catalysts, no deactivation was observedin the course of cyclic variation of steam content and temperatureduring 5-h hours. Hence, for nanocomposite active componentscontaining Pt group metals and/or Ni and complex fluorite-like oxi-des, formation of ethylene as by-product does not deactivate sam-ples. Indeed, the increase of ethanol content in the feed provides ahigh yield of syngas even at short contact times (Fig. 10) withoutperformance deterioration, though ethylene concentration in theeffluent increases from 1.3% (at 5% of EtOH) to 6% (at 23% of EtOH).Note that when deactivation due to coking takes place [16,39,40],activity in ethanol SR declines by 3–4 times within several hours.

Fig. 13. Temperature dependence of H2, CO2 and CO concentrations in effluent foracetone SR on catalysts based upon Ti foil substrates (samples 12 and 13, Table 1).Feed composition 1%C3H6O + 2%H2O + He, contact time 15 ms.

0 1 2 3 4 5 60.00.10.20.30.4

1020304050

C2H4

CH4

CO2

CO

H2

Con

cent

ratio

n, %

1238 V. Sadykov et al. / Fuel 89 (2010) 1230–1240

For oxy-steam reforming of ethanol which is attractive from theheat management point of view, catalysts on monolithic heat-con-ducting substrates with nanocomposite active components (sam-ple 10, Table 1) also provide a high yield of syngas at shortcontact time (Fig. 11). In this case, nearly constant H2/CO ratio�1 can be achieved at a broad variation of H2O/ethanol ratio. Con-centration of ethylene in effluent is below 0.2% agreeing with con-clusion about importance of redox properties of a catalyst fortransformation of C2H4 into syngas.

3.2.4. AcetoneActive components and structured catalysts designed in this

work were found to be also very efficient and stable to coking inthe reaction of acetone steam reforming (Fig. 12). This is veryimportant since acetone as by-product of bio-oil steam reformingis known to be responsible for coking of traditional catalystsincluding Pt/ZrO2 [41,42]. In this reaction, Ni-containing activecomponents also provide the highest performance, which agreeswith a high and stable activity of bulk nanocomposite materialsbased upon NiO/YSZ cermet promoted by doped fluorite-like oxi-des [15]. With a due regard for formation of acetone as by-productin the reaction of steam reforming of acidic acid [41,42], our resultscertainly correlate with a high activity of alumina-supported Ni/La2O3 catalysts in the last reaction [43]. H2 and CO concentrationsin the effluent increase with the contact time achieving a high levelalready at s � 0.2 s, which is certainly attractive for the practicalapplication. The main by-product here is again CH4, with its con-tent in the effluent reaching up to 6% in conditions of tests pre-sented in Fig. 12. Ethylene is present in much smaller amounts(below 0.3–0.5%). For Ni-containing nanocomposite active compo-nents supported on oxide layers protected Ti substrates, a high rateof hydrogen formation was observed even without co-promotionwith Pt (Fig. 13), which again agrees with a high and stable activityof bulk nanocomposites of this type [15].

The same types of nanocomposite active components contain-ing Ni, Pt and doped fluorite-like oxides are efficient and stablein acetone transformation into syngas even when supported onmonolithic corundum substrate (Fig. 14). Similar to the case of eth-anol steam reforming, the main by-product here is also CH4. Atlonger (0.5 s) contact times, only small amounts of ethylene by-product are observed, apparently due to its transformation into

Fig. 12. Effect of contact time on H2 + CO content in effluent for acetone SR onmonolithic catalysts (Table 1). Feed 10% acetone + 50% H2O + 40% N2, inlettemperature 750 �C.

O2 content in feed, %

Fig. 14. Effect of oxygen content in the feed on products concentration in the oxy-steam reforming of acetone on catalyst 11 based upon corundum monolithicsubstrate (Table 1). Contact time 0.5 s, inlet feed 24% acetone + 48% H2O + O2, N2

balance, T inlet 600 �C, T outlet 700 �C.

syngas without forming carbonaceous deposits. Oxygen additioninto the feed only slightly increases hydrogen yield but helps toimprove the heat balance and further decreases the ethylene con-tent thus ensuring performance stability even at a moderate excessof steam which is attractive from the process economy point ofview.

3.2.5. Anisole, sunflower oilFor these feeds a high and stable performance of developed cat-

alysts was demonstrated as well. Some typical results are shown inFigs. 15 and 16. Due to well-known high coking ability of thesefuels, their stable performance was obtained only in the case ofoxygen addition to the feed (oxy-steam reforming). Moreover, onlyunique design of evaporation and mixing unit used in this work al-lowed to obtain stable and reproducible results preventing crack-ing of fuels in supplying lines. The most efficient performance intransformation of these heavy fuels was provided by combination

Fig. 15. Effect of H2O content in the feed on product concentrations in the oxy-steam reforming of anisole on catalyst 10 based upon Fecralloy thin wall foilsubstrate (Table 1). Contact time 0.06 s, T exit 850 �C, feed composition 18%O2 + anisole (5–10%) + H2O (3–20%) + N2 balance.

Fig. 16. Effect of catalyst temperature on the product concentration in the oxy-steam reforming of sunflower oil on stacked layer of catalysts 10 (front part) and 11(rear part). Feed composition 0.7% of sunflower oil + 15% H2O + 20% O2, N2 balance,contact time 0.2 s.

V. Sadykov et al. / Fuel 89 (2010) 1230–1240 1239

of catalysts based on heat-conducting metallic substrates (placedin the front part of the layer, efficiently transferring heat generateddue to fast oxygen consumption) and those based on corundummonolithic substrates (placed in the rear part, provide a high con-version level due to developed surface area). As far as we know,this is the first example of successful transformation of these fuelsinto syngas in the reactors with stationary layers of catalysts.

4. Conclusions

Results of this work demonstrate that nanocompositescomprised of complex oxides (La- or Pr-doped ceria-zirconia solidsolutions, complex perovskite La0.8Pr0.2Mn0.2Cr0.8O3, their combi-

nations with YSZ) promoted by Pt, Ru, Ni or their combination, se-lected by results of short-term screening tests in diluted feeds aspromising catalysts for transformation of gas and liquid fuels intosyngas, retained their activity and coking/sintering stability whensupported on structured substrates (metallic, cermet, ceramic)and tested in real feeds at high temperatures and reagent concen-trations in pilot-scale installations. A proper design of catalysts onstructured substrates and their arrangement within reactors allowto minimize the impact of heat and mass transfer processes andoptimize the temperature profiles thus ensuring nearly equilib-rium yields of syngas at short contact times. For steam reformingof methane, the most promising results were obtained for nano-composite active component La0.8Pr0.2Mn0.2Cr0.8O3 + NiO + YSZpromoted by Ru and supported on compressed Ni-Al foam sub-strate and corundum layer protected Fecralloy gauzes. For trans-formation of liquid fossil fuels (decane, gasoline) into syngas viafast selective oxidation at short contact times as well as for oxy-steam reforming of biofuels (ethanol, acetone, anisole, sunfloweroil), the most promising type of active component is comprisedof Pr-doped ceria-zirconia solid solution promoted by LaNi(Pt)O3.A radial-type reactor combining layers comprised of structuredheat-conducting catalytic elements and high-surface area micro-spherical catalysts appears to be the most attractive for selectiveoxidation of fossil fuels into syngas due to internal heat recupera-tion. Less energy demanding and more prone to coking processesof oxygenates autothermal reforming into syngas can be carriedout in the axial-type reactors equipped with combination of cata-lysts based upon heat-conducting substrates (inlet part) and cera-mic substrates (rear part) with supported nanocomposite activecomponents used in this work.

Acknowledgment

This work is supported by INTAS 05-1000005-7663, INTAS YSF06-1000014-5773, SOFC 600 FP6 EC Projects and Integration pro-ject 57 of SB RAS-Belarus National Academy of Sciences.

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